Methods :
A549 cells were infected with AdV 8, 19, and 37 and cultivated in the presence of serial dilutions of the three different eye drop formulations. The inhibition of virus replication was evaluated by the relative amount of generated AdV protein detected by immunostaining. The anti-viral activity of the three compounds was determined by the lowest concentration needed for 50% inhibition of virus replication (IC50).

Results :
Iota-carrageenan in the tested eye drop formulation NCX4240 is anti-virally active against all three AdV viruses (8, 19 and 37) tested with IC50 concentrations <20 µg/ml. In contrast, the two other products containing either hyaluronic acid or CMC did not show any anti-viral activity at the highest concentrations tested, 300 µg/ml and 400 µg/ml, respectively.IC50 concentrations needed for inhibition of AdV [µg/ml] were for Iota-carrageenan (NCX4240): AdV8 = 19.7, AdV19 = 11.4 and AdV37 = 11.3, for hyaluronic acid (Vismed®): >300 for the 3 strains and for CMC (Carmellose®): >400 for the three strains.

Conclusions :
The newly developed product NCX4240 is anti-virally effective against AdV8, 19 and 37 at concentrations which are 160 times lower than that present in the final product (3.2 mg/ml). Other marketed products (Vismed® and Carmellose®) do not have any anti-viral effect. Based on these encouraging results we suggest testing NCX4240 as a treatment in AdV infected patients in a clinical trial.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.